Wrench



H. A. MEAD Nov. 1, 1932.

WRENCH Filed April 9. 1951 INVENTOR H.A.Me-ad ASL ATTORN EY Patented Nov. 1, 1932 UNITED STATES PATENT OFFICE HOMER A. MEAD, OF TURLOCK, CALIFORNIA, A SS IGNOR TO MASTERENCH CORPORATION, OF TURLOCK, CALIFORNIA, A CORPORATION WRENCH Application filed April 9,

This invention relates to pipe wrenches, and particularly represents improvements over a wrench of that general type shown in my Patent No. 1,7 35,257, dated November 12th, 1929, in which the movable jaw is pivoted in connection with a fixed jaw instead of being slidably relative thereto, as is ordinarily the case.

The principal objects of the present invention are to provide wrenches of this general character constructed so as to have a greater gripping range as to the size of the members to be engaged thereby than was the case with the previous wrench; one in which the jaw retracting spring is mounted in place without the use. of rivets or pins so that the constructing and assembling of the tool is cheapened; and one which in general is cheaper and of a less expensive nature.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claim.

In the drawing similar characters of reference indicate corresponding parts in the several views:

Fig. 1 is a side elevation of my improved wrench showing one of the movable jaw surfaces engaged with a circular element.

Fig. 2 is a fragmentary section of the wrench showing a jaw in its normal or idle position.

Fig. 3 is a similar view showing the other movable jaw surface engaged with a circular element.

Referring now more particularly to the characters of reference on the drawing, the numeral 1 denotes the shank and handle member of the tool which is formed at its upper end as a fixed jaw A, having a row of sharp teeth 2 arranged in a circular curve of substantially 90 degrees extent. The center of this curve is adjacent the outer side edge of the shank and its radius is approximately equal to the width of the shank at that end.

The circular groove 3 is milled in the inner side edge of the shank near the upper end on the fixed jaw, into which groove adjacent its upper end the hub portion 4- of the movable jaw B projects. The hub is pivoted to 1931. Serial No. 528,712

the shank by a cross-pin 5, which is disposed and also being the longer of the two. Both gripping faces, however, are disposed at the same angle relative to radial lines extended from the axis of the pivot to the back ends of the faces, said angle being preferably slightly greater than 90 degrees, asindicated in Fig. 2. Owing to this disposition of the gripping faces and the curved arrangement of the teeth 2, said gripping faces are also disposed in planes parallel to lines tangent to the teeth 2. This double jaw arrangement gives the wrench a wide gripping range, as will be evident, and enables the same to be'eifectively used to engage various sizes of pipe and the like while maintaining the pivot pin 5 within the bounds of the straight shank.

To normally hold the movable jaw at and to return the same to a relatively closed position, I provide a spring between the shank and the hub of said movable jaw. This spring is of the flat hair pin or double leaf type and is mounted in the groove 3. The under leaf 8 of the spring has a. normally greater radius of curvature than the bottom of the groove and only rests adjacent its ends thereon. At its free end said leaf passes between the hub and the bottom of the groove and terminates in a short bend 9, which forms an enlargement incapable of passing between the hub and the groove. The outer leaf 10 of the spring abuts against the hub 1 and also bears against a shoulder 11, positioned on the hub so that the natural expansion of the spring, or the leaves to separate, will turn the movable jaw to a relatively closed position. The leaves are connected to each other at their opposite ends by an integral loop 12, which .95 tendency of the rests on and is always concealed within the groove towards its lower end.

By means of this arrangement of the spring, not only is the desired movement imparted to the jaw, but the spring is held in place without the use of rivets or other holding means. This is because the under leaf cannot be drawn from under the jaw hub in one direction owing to its enlarged end 9, while the outer leaf cannot move in the opposite direction owing to its engagement with the hub and shoulder.

As the spring becomes compressed with the outward turning movement of the jaw B relative to the shank, the under leaf bends and follows the contour of the groove in which it seats. This groove curvature not only forms a smooth unbroken seat for the spring, preventing possible distortion of the same, but allows of the relative sliding movement of the spring as it compresses without any binding of the same being had.

To turn the movable jaw by hand against the resistance of the spring, said jaw towards its lower end is provided with thumb engaging means. This is preferably in the form of a notch 13 depressed in the outer periphery of the aw and merging into a lug 14 which projects outwardly from the normal periphery line of the jaw. Either the notch or the lug alone may be used if desired.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claim.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

A wrench comprising a shank having a fixed jaw on one end and provided in one side near the jaw with a relatively deep groove, a movable jaw member having a gripping face opposed to the fixed jaw and a hub projecting into the groove, and pivoted on the shank, and a relatively flat U-shaped spring mounted in the groove, the outer leaf of said spring at its free end engaging the hub in a manner to turn the movable jaw member to a closed position, and the under leaf extending along the bottom of the groove; the free end of said under leaf passing through the space between the hub and the bottom of the groove and being provided beyond the hub with an enlargement incapable of passing through said space.

In testimony whereof I affix my signature.

HOMER A. MEAD. 

